Chimney flashing

I am reading the metal roof installation instructions. One of the hardest parts I see is chimney (& skylight etc) flashing. There are many good detailed instructions for shingles, but have not seen one for metal (particularly metal villa tile). I am interested in the decra villa tile, which is not flat at all (that's where I see the challenge). Here is their 2-page installation guide for such situations (http://www.decra.com/PDF/InstallGuide-DECRA-VillaTile-5.pdf).
1. Pipe flashing. Would not it be hard to sandwich the flashing metal between 2 layers of tile? Cutting the flashing metal smaller will make the fit easier, but you will risk leaking. Plus, the picture makes it easier by putting the pipe on the high point of the tile, but in reality, the pipe can be on the valley or between. That seems even harder to work with unless you cut the plywood opening big to adjust the pipe-tile position.
2. Chimney flashing. I can see the lower part is easier. It does not need too much work to direct the water on the tiles. But the side and high-end of the chimney are not easy. First, you need to direct water from the high (back) end of chimney to sides (mine is 18" wide) on the side flashing, and make sure it will not run beyond the side flash while doing down hill along the side flashing. Second, you need to direct that water on the tiles when the side flashing meets the lower chimney end. I see that it would be a little easier if the tile valley is just on the side of the chimney, but you do not have a good control of that.
Do you have any suggestions or any good installation guides?
Thanks,
John

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I am going to open this up to anyone out there with tile profile experience. Also, I am not sure who the technical person is at Decra these days but historically they have had folks pretty adept at helping in these areas.

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I have installed many similar profiles, for example Metro Roman and Dural Loc Continental. Most products have similar installation methods when dealing with a profile such as these. Your best bet is to contact Decra and ask for clarification.
We typlically bend the roof tiles up to the side walls of the skylight / chimney a min of about 2". Then we either tuck it up under the existing flashing if its roof to wall type metal. If your dealing with bricks you could remove the existing step flashing and install some new flashing. We typically do not remove siding to replace the existing roof to wall metal unless there is obvious problems with it.
I see Decra has a tile pan type asscessory in there diagram for the side wall. Each product has it's own accessories and this is why i would recommend you contact Decra. Find out how they want you to flash it or if its an optional item. Lets say your going over a wood shake roof with full battens ( 1x4 and 2x2). Once you lay your grid down on the exisiting old roof you may not be able to get under an exisiting roof to wall flashing. In this case, a J channel or tile pan type flashing would benefit your installation. Again, check with Decra to find out what they approve in your situation or even ask your contractor. Also, the bird stop detail at the rear of the chim / skylight and the top row / bird enclosure for the front of these two situations is similar across products of this profile type. The installtion method will slightly vari from product to product.
The base flashing for the vent pipes should be formed to fit the tile profile, it does not have to be exact. You form it enough so that when your cover pan (what I call the roof tile that covers the vent flashing) is installed, your roof plane does not take on the appearance of a volcano near the pipe you just flashed. Again, check with Decra for clarification on how they expect them to be done. I know Metro has a detail for thier Roman Tile that is rather specific.
No luck on u-tube either, i didnt see anything showing the details that would help you.
Andy

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1. Pipe flashing. Would not it be hard to sandwich the flashing metal between 2 layers of tile? Cutting the flashing metal smaller will make the fit easier, but you will risk leaking. Plus, the picture makes it easier by putting the pipe on the high point of the tile, but in reality, the pipe can be on the valley or between. That seems even harder to work with unless you cut the plywood opening big to adjust the pipe-tile position.
Position of the pipe(high point/low point) makes no difference. Once the underpan is install over pipe, the Pipe Boot can be installed where ever it needs to be positioned. Because the panels are scalloped, it typically works best to use a flexible base pipe boot. A traditional pipe boot normally used with asphalt shingle with an aluminum base works best as it allows you to form the pipe boot to the shape of the tiles. So long as the proper relief cuts are made at the nose of the overlying panel, flashing should be watertight. If the pipe falls on a horizontal lap(top on one panel/bottom of another) then two underpans may need to be used.
2. Chimney flashing. I can see the lower part is easier. It does not need too much work to direct the water on the tiles. But the side and high-end of the chimney are not easy. First, you need to direct water from the high (back) end of chimney to sides (mine is 18" wide) on the side flashing, and make sure it will not run beyond the side flash while doing down hill along the side flashing. Second, you need to direct that water on the tiles when the side flashing meets the lower chimney end. I see that it would be a little easier if the tile valley is just on the side of the chimney, but you do not have a good control of that.
This detail is a bit more challenging. Process will vary depending on how the panel scallops line up with the Chimney. At the end of the day what you need to do is close of the front side of the chimney with Bird Stop Ridge flashing and maybe some type of apron flashing over it. The Villa channels need to be positioned so they can drain on top of Apron flashing or the panels below. Panels coming into the side of the chimney will be cut and terminate into the Villa Channel. On the top side of the chimney a large metal pan should be installed across the back of the chimney. It should run flat to the deck and be bent up the chimney. It should also extend past the sides of the chimney and be lapped and folded over and into the Villa Channels coming up the side. This process will allow water from above to hit the top pan, run side to side, drain into the Villa Channels and then carry down the sides and drain out on top of the panels below.

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I have not fully digested your replies yet. But would like to say THANK YOU to everyone of you first.
I did contact Decra after I saw Todd's reply, and got a response as well. Their response has less details than yours here. Basically, for pipe flashing, they suggest "PVC single ply flashing". Does anyone know what this is (Is this the one? http://www.youtube.com/watch?v=cDshRC22x-I) and how good it is?
I have a question about info's reply: "Position of the pipe(high point/low point) makes no difference. Once the underpan is install over pipe, the Pipe Boot can be installed where ever it needs to be positioned." By location I meant relative to the tile -- the tile has a w-shape (more like an S turned 90 degrees). Imaging the pipe penetrates at the center/middle of W. That's what I meant by "high" point. In this case, you can cut down the underpan's "^"-part down to let the Pipe Boot sit. But if the pipe comes out at the "v" part of W, then there is not much you can lower the Pipe Boot. Please bear with me as I am imagining in my head only.
About chimney flashing. Before your wonderful replies, I was thinking about flattening the upper part of the tile just below the chimney to put it under the flashing, and flatten the lower part of the tile just above the chimney to avoid wind-driven rains and birds getting in. Does that make any sense at all?
Again, many thanks to you all; I will look through all your replies carefully.

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I wouldnt use that type of flashing for a metal roof, its more for flat or low slope type applications.
I did find a video from Metro showing the Roman tile application around a chimney. This should help even though it is not Villa, same principles apply to installtion of similar profiles so this may help you.
http://www.metroroofproducts.com/chimney_panels.cfm
Andy

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Oops, i should have linked all the vids for that profile.
http://www.metroroofproducts.com/MetroRomanTileInstallDetails.cfm
I also didnt noticed until after i posted that they had the full chimney installation broken up over 2 or 3 vids.
Hope that helps.
Andy

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